I'm not a professional But, I am a female and an older one at that. Welcome to your 30's, that's when your body starts to turn on you,lol. I was as skinny as a rail and could eat anything without gaining an ounce until then. The cellulite happens 95% in women and only 5% in men Not Fair hua. I have heard that the healthier your diet is the less you will have, that it has more to do with diet than excerise. I hope that's helpful!
I used to be skinny too... until I reached 40, I started paying for all those chocolate cookies!! I got a little lazy too!! I started working out again and I'm seeing results! Like u I've never been worry about weight but we shouldn't be careless either...
For me a 30 mins circuit did awesome! If u like workout videos I suggest T25, it's 25 mins + 3 mins cool down. It's great and u work at your own intensity.
Sigh. I'm in the same boat, except I'm a little shorter. I have found, though, that a regime of cardio and strength help. I only do 20 mins of cardio and 20 minutes of strength and I noticed a difference in about a month. Hope that helps!